adds backend and frontend config sections

new defined types:
haproxy::frontend
haproxy::backend

haproxy::backend uses haproxy::balancermember the same way
haproxy::listen does. I'm not sure I like overloading that, but it
should work.
ruby 1.8.7 compatibility
reorder the frontend and backend sections a bit
changing the order a bit more

kinda regretting not making a separate haproxy::backendmember type
fix tests for frontend order change
remove deprecation warnings from templates
Merge pull request #37 from 3dna/frontendbackend

adds backend and frontend config sections